The present invention relates to a new and distinct cultivar of ornamental Sage plant hereinafter referred to by the cultivar name Salvia ‘Crystal Blue’ or as the new plant. The new plant was discovered on May 19, 2010 in a commercial garden planting of Salvia ‘May Night’ in Lake of the Hills, Ill., USA. The new plant was an isolated whole plant of flowering size. The new Salvia was isolated put under further evaluation at a nursery in Zeeland, Mich., USA during the summer of 2012 for the unique traits to be studied. The new plant was then further evaluated and asexually propagated by tip cuttings at the same nursery in Zeeland, Mich. The resulting asexually propagated plants of Salvia ‘Crystal Blue’ have been found to be true to type and stable in successive generations.